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Consider the following homogeneous differential equation. dy/dx = y - xy + x. Use the substitution y = ux to write the given differential equation in terms of only u and x. Solve the given differential equation. (Enter your answer in terms of x and y.)

User Kidbrax
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Final answer:

To solve the homogeneous differential equation by substitution, express y in terms of ux, differentiate, and substitute into the original equation. Separate variables and integrate both sides to find u as a function of x, and then substitute back to express y in terms of x.

Step-by-step explanation:

To solve the given homogeneous differential equation dy/dx = y - xy + x using the substitution y = ux, first express y as ux and differentiate both sides with respect to x:

Since y = ux, we then have dy/dx = u + x(du/dx).

Substitute y and dy/dx in the original equation:

u + x(du/dx) = ux - ux^2 + x

Simplify and group like terms to obtain an equation involving u and x:

x(du/dx) = x - u^2x^2,

which simplifies further to:

du/dx = 1/x - u^2x.

This equation can be solved by separation of variables:

du/(1 - u^2x^2) = dx/x.

Integrating both sides gives:

½ ln |1 - u^2x^2| = ln|x| + C,

where C is the constant of integration. Solving for u and then substituting back for y yields the general solution of the differential equation.

User Umbersar
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